Characteristic values of tensile strength (TS) and Brinell hardness (BH) of different forms of iron

Reference 1: TS (MPa) and BH (Brinell).

Reference 2: Iron whiskers, Ausformed (hardened) steel, Martensitic steel, Bainitic steel, Pearlitic steel, Cold-worked iron, Small-grain iron, Carbon-containing iron and Pure, single-crystal iron.

Source: http://en.wikipedia.org/wiki/Iron#Biological_role